The explosive growth of Internet traffic has brought a bandwidth hungry and a critical need to manage huge volumes of information. Although fiber-optic communications have enjoyed almost unprecedented success in the past decade, to sustain the long-term growth of information transfer capacity, technological breakthrough must come from new materials, fundamental optical devices and subsystems. There is an intensive pressure to develop cost-effective, high quality integrated photonics circuits, allowing denser, faster, cheaper, more efficient optical signal processing.
In order to make full use of the wide optical bandwidth provided by optical fiber, more wavelength channels have been used in wavelength division multiplexed (WDM) optical networks. Among others, WDM optical demultiplexers, wavelength routers and optical amplifiers are fundamental devices in WDM optical networks. Present opto-mechanical switches and present thermal tuning of silica-based array waveguide grating (AWG) in use are not fast enough to perform optical packet switches. InP-based AWG were attempted, which may be switched by carrier injection and potentially have higher speed. However, due to high refractive index of the material and small waveguide size, InP-based AWG have unacceptable high optical loss and temperature sensitivity.
There is a need in the art for improved method and apparatus for optical communications, particularly high-speed optical switches and wavelength routers, that have acceptable amounts of optical loss and temperature sensitivity.